Answer:
Endospores are the non-reproductive, tough structures formed by some gram-positive bacteria.
The bacteria can form the endospores in nutrient-deprived condition and extreme environmental conditions.
Since the endospores are resistant to the environmental stresses, desiccation, gamma radiation and other factors this ensures the survival of the bacteria for a long period of the environmental stress. This protects the genetic material of the bacteria in the harsh conditions thus, it ensures the transmission of bacteria in a population.